| Guido van Rossum | 85a5fbb | 1990-10-14 12:07:46 +0000 | [diff] [blame^] | 1 | /* Bitset interface */ |
| 2 | |
| 3 | #define BYTE char |
| 4 | |
| 5 | typedef BYTE *bitset; |
| 6 | |
| 7 | bitset newbitset PROTO((int nbits)); |
| 8 | void delbitset PROTO((bitset bs)); |
| 9 | /* int testbit PROTO((bitset bs, int ibit)); /* Now a macro, see below */ |
| 10 | int addbit PROTO((bitset bs, int ibit)); /* Returns 0 if already set */ |
| 11 | int samebitset PROTO((bitset bs1, bitset bs2, int nbits)); |
| 12 | void mergebitset PROTO((bitset bs1, bitset bs2, int nbits)); |
| 13 | |
| 14 | #define BITSPERBYTE (8*sizeof(BYTE)) |
| 15 | #define NBYTES(nbits) (((nbits) + BITSPERBYTE - 1) / BITSPERBYTE) |
| 16 | |
| 17 | #define BIT2BYTE(ibit) ((ibit) / BITSPERBYTE) |
| 18 | #define BIT2SHIFT(ibit) ((ibit) % BITSPERBYTE) |
| 19 | #define BIT2MASK(ibit) (1 << BIT2SHIFT(ibit)) |
| 20 | #define BYTE2BIT(ibyte) ((ibyte) * BITSPERBYTE) |
| 21 | |
| 22 | #define testbit(ss, ibit) (((ss)[BIT2BYTE(ibit)] & BIT2MASK(ibit)) != 0) |